Rangers' abject start to the season continued as former Celtic striker Oh Hyeon-gyu's goal - and Mohamed Diomande's first-half dismissal - helped ​Genk to a 1-0 Europa League win at Ibrox.

Under-pressure head coach Russell Martin was seeking successive victories for the first time, but his team were second-best for long spells against the Belgian side who missed a host of chances.

In recent seasons, this competition has brought welcome relief from domestic indifference for Rangers. But it quickly became clear even that would allude them this time.

It was another miserable outcome for Martin, who just can't find a way to build momentum or positivity.

Rangers were already on the back foot before Diomande lunged rashly at Zakaria El Ouahdi shortly before half-time. A straight red card seemed justified.

Earlier, it had appeared John Souttar had given Ibrox the lift it needed when his angled header flew towards the net. But Bryan Heynen produced an incredible overhead kick clearance to deny him.

It was as good as it got for the Scottish Premiership's 11th-placed side.

Oh - scorer of 12 goals in 47 Celtic appearances a couple of seasons ago - somehow missed when all alone in the area. Patrik Hrosovsky then struck a post.

Rangers then thought they had a penalty when James Tavernier's header struck the raised arm of Joris Kayembe but, after a long review, Tavernier was deemed to have given him a slight push.

After Diomande's exit, the drama continued when the Rangers captain lost Yaimar Medina, then caught him, and a penalty was given. To Rangers' relief Jack Butland denied Oh from the spot.

But the decisive moment came when Oh escaped a dithering defence and fired across the exposed goalkeeper.

The Korean still had time to miss from a yard on the slide, then have another ruled out for offside as Genk hunted a second.

Rangers gamely chased an unlikely leveller, and substitute Connor Barron had a late strike brilliantly diverted away, but it turned into another night of torment for the Ibrox side and their fans.

Normally, European nights at Ibrox are electric.

But it felt flat in the build-up here, with a notable absence of home supporters in sections of the stadium. Anger and outrage are difficult to deal with but apathy can be even more acutely felt.

Fan protests were less evident after the weekend League Cup win over Hibernian, not that the tide has turned on that front by any means. Certainly not after this.

This was seen as an ideal opportunity to build some momentum against a side who appeared to be struggling domestically in the same manner as Rangers.

They didn't look it as they surged at the Ibrox side time and again.

Martin's team had one or two moments of threat but, in truth, Genk were worthy winners and not just because Rangers were a player down for the second half.

Defensive frailty was all-too evident and ought to have cost them more than it did.

Youssef Chermiti starting didn't pay off, but the service was way light.

The barnstorming type of Europa League occasion these fans have become accustomed to was badly missing as Martin's side once again struggled.

That's four wins from 14 outings. Four defeats in their last seven. That's not the standard Rangers demand.

Only wins, and lots of them, will change things if the support are to be re-engaged.

Rangers head coach Russell Martin: "I'm frustrated. The red card changed a lot, but I'm proud of the players in the second half.

"I asked them to be really aggressive after the sending off, not just try and defend for 45 minutes. Genk didn't cut us open, we weren't defending relentlessly.

"The longer the game goes on, if we actually dominate the ball, we create a lot more. We'll get there.

"We had 10 men for a long time, I think Jack [Butland] only had two saves to make in the second half. I thought we had some really good performances."

Rangers goalkeeper Jack Butland: "There were some bright moments to start with, but we've gone down to 10, given away opportunities, and in Europe, that is difficult.

"In saying that, we didn't go under, we didn't fall apart. But there was not enough good stuff there tonight. And ultimately we concede a poor goal in a game where they didn't threaten us all that much or cut us open.

"So it's an opportunity we missed, for sure."

Rangers return to Premiership action on Sunday at Livingston (15:00 BST). By then, they could even be bottom of the division.

After that, they travel to face Sturm Graz in Austria next Thursday.

Genk return to domestic league action before hosting Ferencvaros in their next Europa League tie.